Hydraulic leveling and controlling device



Aug. 29, 1950 c. N. ADAMS 2,520,265

HYDRAULIC LEVELING AND CONTROLLING DEVICE Filed June. 23, 1945 2 Sheets-Sheet 1 INVENTOR. Cf JfHdams BY i Y Aug. 2Q, 1950 c. N. ADAMS 2,520,266

HYDRAULIC LEVELING AND CONTROLLING DEVICE l 2 Sheets-Sheet 2 Filed June 23, 1945 10 gz I /45 f *7 2156.10

9a A INVENTOR. cMdamS HTTYS Patented Aug. 291 1950 HYDRAULIG LEVELING AND CONTROLLING DEVICE `Chrisltopher N. Adams, San Joaquin lCounty, Calif'.

Apnlicction June.- .2.3, 194.5. Serial.. Nie. 6 01,143.2.

I 2=Claims- This invention relates. te leveling. mechanisms for the blades. ol levelers. to. automatically maintain such blades level irrespective of the transverse level oi the glound being traversed by the imp1ernent, and particularly represents a moeliiied arrangement` over what is shown in my Patent No. 2,284,550.

In this patent. means are provided to control the level ci the blade by mechanical Or electrical devices, and my principal object now is to. provide a hydraulic. control mechanism for the purpose.

Though initially designed for leveler use, the mechanism is also suitablev for use to keep any movable part` level. or at a cOIlSlaIlt angle from levelL when such part is mounted on a base sub.- J'ect to tilting or variation from a vertical or horizontal plane.`

I have also provided an improved form of uid control valve as. all important feature of the mechanism.

A further object of thev invention is toA pro.- duce a simple and inexpensive device, andyet one which will be exceedingly eifective for the purpose ier which it is designed'.

These objects are accomplished by means. of such structure andv relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings similar characters oiv reference indicate corresponding parts in the several views:

Figure 1 is a rear end outline of a l'eveler equipped with inyimproved hydraulic leveling mechanism.

Figure 2- is an enlarged sectional elevation of the hydraulic control mechanism, part-ly diagrammatic, andshowing the preferred form of controlval-ve unit.

Figure 3 is an endl elevation of therco-ntrolunit with the cover plateremoved.

Figures 4 to- 8- are diagrammatic cross sections of the control valves on lines 4 4, 5 5, 6 6, 1 and 8 8; respectively, of Fig. 2.

Figure 9 is a. Sectional; elevationo a. modified form of valve unit and control system.;v generally.

Figure l is a cross section of the valve on line i-lziofFig. l.

Referring now more particularly to the characters` of reference on the drawings, and at pres ent to the structure shown, inv Figs. L to 8., the level to which my improved hydraulic control mechanism. is applied' comprises essentially a Wheel mounted main frame i' from the rear end of which a transverse leveler blade 2 is suspended on a. longitudinally extending centralA pivot; 3. Links 4 extend; upwardly from the blade en opposite sides of the pivot and are connected at 2 their. upper ends to a cross. beam 5 centrally pirated on an auxiliary frame e.. As here sli-Own,

`an arm i depends from the beam. 5 and is e011.-

Iie'ed to. the, piston rod t oi a double. acting hydraulic cylinder 9 extending transversely of' and suitably mounted on the frame l. This cylinder has liquid passage, pines Ill. and. H leading to the ends of the. cylinder. on opposite. sides of the. piston l. 2...

1t vvill o fcourse be evident that when the QSQrl. is moved in one direction or the, other by nuid in 1211e, cylinder the cross beamand blade 2 will; be correspondingly swung in a transverse vertical plane and this movement is contrclled by a change of transverse level ci the ira-me IV the implement as a whole, by the following structure:

Fixed in connection with the arm 'l' or other part which swings ortilts with the bladeis a valve unit which comprises a casing i3 having a rotor it therein whose axis extends lengthwise of the implement. 'lll-1e rotor is hollow and is closed at loo-th ends with a cross wall. central-ly et its ends and thu-s forming separate internal chambers l@ and il. in the. valve rotor.

An arcuate. port le in the valve adjacent one end: provides constant communication between the chamber li and a pressure pipe i9; connected to. the valve. casing and leading from. a conventional pressure pump, Similarly an arcuate port. 2st in the. valve adjacent its. opnosite end cr idee constant ccminnnication hetwefc. the chercher Iflf and aretu r1. Dise 2'2- connecteii4 to the velveoasine and; lea-.dine baci: to. the crime- Eorts '3- the. valve on opposite .es or. the wall l5= com unieate with a bypass. the.; valve casing only when the valve is in. its. normal posi-- tion. zr/When; the blade is horizontal. The area of; the ports 231 is. sufdciently large to.. take the full. 0f the pipe i9- but. are made relatively narrowv arcuately, as shown in Fig.1 6 so, that they Will close. with only a Slighty rotary movement of. the valve from its normal position.

A normally closed port 25 in the casing i3 is Connected by a eine 2.6 with the eine it.; a port 2l in. they valve chamber. le being disposedl to one. side 0i. the. plane of the. ports. 2.3. and. adapted to register with the port, 22e? when. the valve is rotated in one direction irorn itsl normal'l position. Another normally closed' port 28; in4 the casing i3 ijs connected by a pipe 29 withA the pipe lll; a, port 3Q in the chamber Hi being disposed on the opposite side of the` plane of the ports 23 and' adapted to register with the port 2%" when the valveisrotated in the other directionl from its normal position.

Similarly`4 anotherA normally closedv port 3i: in the valve casing is connected1 vtothe pipe lil byfa pipe 32; a port 33 in the chamber I6 and disposed on said opposite side of the .plane of the ports 23 being adapted to register with the port 3| when the valve is rotated in said other direction. Another closed port 34 in the valve casing is connected by a pipe 35 with the pipe Il; a port 36 in the chamber Il being disposed on said one side of the ports 23 and adapted to register with the port 34 when the valve is rotated in said one directicn.

It will therefore be seen that the liquid as pumped may normally flow unobstructed through the valve, but as soon as said valve is turned somewhat in one direction or the other the liquid is forced into the cylinder 9 from the chamber I6 either from the pipes 26 or 32 on one side or the other of the piston I2, While liquid is discharged from the cylinder on the opposite side of the 4piston and into the chamber l1 and thence to the return pipe 22 either from the pipe 29 or the pipe 35. If desired a suitable check pressure relief valve 31, resisting normal pump pressure and opening toward the chamber I1, may be mounted in the wall l5.

The above described movement of the valve, which obviously controls the tilting of the blade 2 is controlled or actuated by the following means:

The valve at one end is provided with a pinion 38 meshing with a relatively large gear 39 which is mounted on a stub shaft 40 fixed in a lateral extension 4I of the housing I3. A pendulum 32 depends from and is fixed with said gear, the extension 4l enclosing and protecting the pendulum, as shown, and also serving to limit its throw beyond points which will fully open the valve. By reason of the relative sizes of the gear and pinion, a slight swinging only of the pendulum will impart a relatively large amount of rotation to the valve, or so that the different ports will be quickly brought into register with each other. It will be noted that in the above description it is assumed that the pendulum swings. Actually of course the pendulum remains stationary while the implement and the valve case secured thereon rotate about the axis of the pendulum.

The housing extension 4l is preferably oil-tight, so that the pendulum may be immersed in oil, to provide uniform and steady movement thereof.

With the above described valve arrangement the pump is only under load when the cylinder is to be actuated. In the valve structure shown in Fig. 9 on the other hand the only normal flow through the valve l4a is past a pressure relief valve 31a disposed in the central wall I5a. This valve has only two normally closed ports 43 and 44 on opposite sides of the wall a. The port 43 is adapted to alternately register with ports 45 and 46 in the valve casing 13a which are connected to the opposite ends of the cylinder 9a, while the port 44 is adapted to alternately register with ports 47 and 48 in the valve casing which are connected to opposite ends of the cylinder in the reverse order` to the connection of the ports 45 and 46 therewith, as shown. This valve of course is pendulum controlled in the same manner as the first described type.

While the valve units above described have been initially designed for the purpose recited in this specification, it will be obvious that their utility is not conned to this particular eld, and they may be of value in controlling the actuation of any double acting hydraulic or fluid mechanism, and whether gravity-actuated control is employed or not.

From the foregoing description it will be readily seen that there has been produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims,

Having thus described the invention, the following is claimed as new and useful and upon which Letters Patent is desired:

1. In a leveler having a frame and a transverse leveling blade mounted on the frame for relative swinging movement in a transverse vertical plane, hydraulic means to swing the blade, including a double-acting hydraulic cylinder having a piston rod projecting therefrom and connected to the blade mounting, a liquid pressure circulating system connected to the ends of the cylinder, a movable valve interposed in the system to control the liquid flow to and from opposite ends of the cylinder in alternating order, a pendulum mounted on the blade mounting for swinging movement in a transverse plane, and connecting means between the pendulum and valve to move the latter upon a relative swing of the pendulum from a normal position, and an oil tight case in which the pendulum is mounted whereby the pendulum may swing in a bath of oil.

2. A land leveler including a ground supported main frame, a leveling blade pivoted substantially midway of its length tc the main frame and transversely of the latter, an auxiliary frame supported on and projecting upwardly from the main frame, a cross beam pivoted substantially midway of its length to the upper end of the auxiliary frame, a link pivoted to each end of the cross beam and to the blade, a depending arm fixed to the cross beam substantially midway of its length, a fluid pressure motor comprising a cylinder, a piston therein and a piston rod on the piston, the cylinder being pivotally connected to the main frame and the piston rod being pivotally connected to the arm, a fluid pressure circulating system connected to the ends of the cylinder, a rotary valve in said system operative to alternately admit fluid pressure to opposite ends of the cylinder, said valve being fixed to the arm and being swingable therewith, a pendulum, means pivotally suspending the pendulum from the arm for swinging movement relative to said arm and transversely of the direction of travel of the leveler, and connecting means between the rotor of the valve and the pendulum and effective to operate the valve upon relative swinging movement of the arm and pendulum.

CHRISTOPHER N. ADAMS.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 539,466 Winter May 21, 1895 1,272,285 Manley July 9, 1918 2,023,765 Manseld Dec. 10, 1935 2,204,033 Austin June 1l, 1940 2,210,144 Day Aug. 6, 1940 2,278,081 Kramer Mar. 31, 1942 2,284,550 Adams May 26, 1942 2,377,278 Stephens May 29, 1945 

